  <tr id="cart_item_<%=cart_item.product_id%>">
  <td>
    <%= image_tag url_for_file_column(Product.find(cart_item.product_id), "image_url","thumb"),:class=>'product_img' %>
  </td>
  <td><span class="item"><%= h(cart_item.name) %></span></td>
  <td>
    &times;<input  type="text" value="<%= cart_item.quantity %>"  size="1" id="cart_quantity_<%=cart_item.product_id%>" onkeyup="changeQuantity(<%=cart_item.product_id%>)"   />
  </td>

  <td class="price" id="cart_price_<%=cart_item.product_id%>">
    <%= cart_item.price %>
  </td>
  <td>
    <a href="javascript:void(0);" onclick="removeFromCart(<%=cart_item.product_id%>);" >
      <img src="/images/cart_delete.png" alt="删除" title="删除商品" />
    </a>
  </td>
</tr>